N729TG

On October 12, 2018, about 1045 central daylight time, a Cirrus SR22 airplane, N729TG, impacted a parking lot shortly after departing the Midland Airpark (MDD), Midland, Texas. The pilot and passenger received minor injuries, and the airplane was substantially damaged. The airplane was registered to and operated by TJG Equipment, LLC under the provisions of Title 14 Code of Federal Regulations Part 91 as a cross-country flight.

The pilot reported that after departure and about 500 ft above ground level, the engine "surged". He turned back toward the airport and the engine lost power. The pilot recognized the airplane would not make it back to the airport, so he deployed the Cirrus Airframe Parachute System (CAPS). The airplane descended under the parachute into a parking lot and impacted a parked automobile.

The airplane was recovered to a salvage facility. An engine examination was then conducted by the NTSB Investigator in Charge (IIC), and technical representatives from the engine and airframe manufacturers. A visual inspection and borescope examination of the engine was conducted: a damaged propeller and minor damage to the exhaust system was noted. In order to facilitate an engine test run, a replacement propeller was installed, and a fuel can was plumbed into the airplane fuel system. An engine run was then conducted, and the engine started without hesitation. The engine was operated about 1,000 rpm to bring the engine up to operation temperatures. During the engine test run, full throttle was applied: manifold pressure stabilized at 39 inHg and fuel flow reached 49 gph. [The engine manufacturer specifications are 36.6 inHg and 37.5 gph, with Cirrus specified a 40.5gph limit].

After the engine run, the turbocharger controller and wastegate actuator were removed from the airplane and sent to the manufacturer for additional testing. It was also noted that during the wastegate actuator removal, the wastegate valve appeared "stuck". After moving the valve, it appeared to move normally.

The airplane's parachute was also removed and sent to Cirrus for a performance and conformity inspections.

The airplane's recoverable data module (RDM) was downloaded, and a review of the data noted that on the accident flight and previous flights, the engine's fuel flow was high, including near or above the maximum limit. A review of the airplane's maintenance records revealed a maintenance entry dated July 18, 2018, that annotated the manifold pressure was set to 36.5, and fuel flow to 41gph, and rpm to 2,500, per Cirrus aircraft maintenance manual 5-30. There were no additional entries that indicated the fuel flow was later changed.

The wastegate actuator and turbocharger controller were bench tested at Hartzell's Engine Technologies (HET) facility, in Montgomery, Alabama, with representatives from the NTSB, FAA, and HET present. Both units operated normally, with no discrepancies noted that would have affected normal performance.

The engine was removed and shipped to the manufacturer's facility where it was placed in an engine test cell. The NTSB IIC and technical representative from the airframe and engine manufacturers conducted the test. The engine was started and ran at various power settings. It was noted that fuel flows were high, enough so that the engine would run rough, but did not experience a total loss of power. A small amount of black smoke was also observed during portions of the engine test run. Later during the test run, adjustments were made that lowered fuel flow; the engine appeared to run normally, without black smoke nor roughness.

A review of Cirrus support publications revealed two publications that address potential issues with engine high fuel flows:

Service Advisory SA19-01, Subject: High Boost/Prime Altitude Lockout Software Condition, which advises that high boost/prime mode be avoided in-flight, below 10,000 ft.

Service Bulletin SB2x-42-17, Subject: 42-20 INTEGRATED MODULAR AVIONICS - Perspective S/W Update, which provides a 10,000 ft altitude lockout feature; and a high fuel flow CAS message, at 42 gph.